Lava Micro FlexDrive Driver (lavadrive2) fits pens

[iewed]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Payment sent for 1!
I can't wait to use this to power my first Blu-Ray

 

[jayrob]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Edit: I think it was the dead dioed that was my problem, not the driver.

Hi drlava, sorry to have to bother you with this but something is not making sense to me. Of the 4 FlexDirvers that I bought, 2 were blu-ray. (marked 'B' on the back). I wanted to adjust the driver to 90mA's, so I am using a dead blu-ray diode for a load. Both of the drivers measured about 346mA's when I tested them. The small pot didn't do much. I turned it about 1/2 turn either direction. It went down to about 336mA's?? Could these be marked wrong? They all 4 look the same visually. Maybe they are Red drivers? What is your opinion?  
Thanks,  
Jay  

 

[Things]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

wow nice drivers lava!! Would these fit in a core barrel and run a BR off 2 AAA's? I dont need super long runtime, just a small laser

 

[phenol]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

jayrob, just a thought... what's the cause of death of ur load? if the junction is shorted and there's no drop across it, the driver may not work properly ( it didnt work with my experiments with a sepic converter) ... :-/

 

[jayrob]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

jayrob, just a thought... what's the cause of death of ur load? if the junction is shorted and there's no drop across it, the driver may not work properly ( it didnt work with my experiments with a sepic converter) ...  :-/

This is a 6 X diode that died from a charged cap. OUCH! I connected the diode to a DDL driver as well. It measured the expected current. When I first tested the FlexDriver, I had 2 X 3.0 volt primaries in the Kenom barrel. Then I tested the drivers with a single 3.6 volt battery as in the picture. The single battery gave the same current as the two batteries did.
Jay

 

[phenol]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

well, DDL's driver will source the preset current even if the load is a dead short circuit, but this may not be the case with the switching-mode driver. you could verify this by measuring the voltage on the dead 6x ( :'( ) bluray or swap it with 5-6 1n4001 in series

 

[jayrob]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Hey I just tried a dead red open can diode with the single 3.6 volt battery. It allowed me to adjust to the 90mA's that I wanted for a blu-ray. So, the 6 X diode was the problem I guess.

Now for the question.... I am planning to use a blu-ray dioed at 90mA's with 2 X 3.0 volt batteries and a silicon diode. Since I used the red diode/single battery for the adjustment to 90mA's, will the driver differ in current when I use the 2 battery/blu-ray? Or should it stay at the 90mA's?
Jay

 

[phenol]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

if all is ok, it should stay at 90mA for the entire range of operating voltages (if the load is 'meaningful'). mimic the bluray with 5-6 Si diodes in series and see for yourself

 

[jayrob]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

if all is ok, it should stay at 90mA for the entire range of operating voltages (if the load is 'meaningful'). mimic the bluray with 5-6 Si diodes in series and see for yourself

Supply and load will be different. The test was about 3 volts supply using a red diode. And I will be using a blu-ray diode with 5.5 volts supply.

Just hoping that someone would already know the answer to this question for this driver so I don't have to connect a bunch of silicon diodes together...
Jay

 

[IgorT]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

The current should stay the same. Everything is within the drivers capabilities.

But the readings you got with the dead diode were indeed strange. I hope you did not power the driver up without a load? Dead diodes can be useful for testing sometimes, but if one goes open circuit, it can kill a switching driver like this. The driver should always provide the same current no matter what the load or battery voltage (within limits).


Also, dead diodes can sometimes change in Vf. As Phenol said, you should have measured the voltage across the diode, when you got that high current. Use dummy loads for testing, those won't die nor change in Vf.


Make dummy loads out of different numbers of regular diodes (like 3x and 6x 1N4001) and try the driver at the same setting on both. If the current doesn't change with the Vf of the load, the driver is fine.

 

[IgorT]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

so I don't have to connect a bunch of silicon diodes together...

Yeah, that's just too much work.. :

If you're playing with lasers, you should already have silicon diodes soldered together.. Especially, if you care about your driver or your LDs. I've been careless before, and i always regretted it.

 

[jayrob]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

[quote author=jayrob link=1209418066/45#56 date=1210832627]so I don't have to connect a bunch of silicon diodes together...

Yeah, that's just too much work..  :

If you're playing with lasers, you should already have silicon diodes soldered together.. Especially, if you care about your driver or your LDs. I've been careless before, and i always regretted it.[/quote]

Lol! I guess since I'm starting to play with these new drivers, I'll have to solder up some test loads. I have never needed to do this with the DDL circuits because I just use my DMM and short across the leads. (I know, wrong way to do it) But my DMM has safety features to protect it, and it is an accruate reading.

Thanks for your guys' help!
Jay

 

[drlava]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

wow nice drivers lava!! Would these fit in a core barrel and run a BR off 2 AAA's? I dont need super long runtime, just a small laser  

Yes!


And thanks for fielding the questions guys you are correct, the current output will stay the same across batteries and loads (within the specified limits).

 

[IgorT]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

And thanks for fielding the questions guys you are correct, the current output will stay the same across batteries and loads (within the specified limits).

BTW, is it possible, that through a short (or with very low Vf), the current would change with this driver?

 

[drlava]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Yes, the current would ramp up to max if the Vf drops below 2.4V. This is why a dummy load is necessary for pre-setting the current, and the current can't be measured by simply shorting a multimeter across it.

 

[IgorT]

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Interesting.. Looks like that 6x BR writer diode from Jayrob really must have changed or even become a short....